Timing mechanism



Feb. 9, 1943. A. R. HUTT TIMING MECHANISM 4 Sheets-Sheet 1 Filed Sept. 15, 1940 ji fy l L l l I L l I.

aQ/nwnl r. Arthur R. Hufi Fdlm 9 A. R. HUTT TIM'ING MECHANISM 4 Sheets-Shee t 2 Filed Sept. 16, 1940 mm mx Q mm i ww iw Feb. 9, 1943. A, R. HUTT 2,310,527

TIMING MECHANISM Filed Sept. 16, 1940 4 Sheets-Sheet 3 13%. 9, 1943. A HUTT TIMING MECHANISM FiledSept. 16, 1940 4 SheetsSheet 4 tQ ITUMI-IOT. Arthur R. Hun

Patented Feb. 9, 1943 TIMING MECHANISM Arthur R. Butt, Thomaston, Conn., assignor to General Time Instruments Corporation, New York, N. Y., a corporation of Delaware Application September 16, 1940, Serial No. 356,891

15 Claims.

appliances wherein the circuit to the cooking element is closed at a predetermined time and opened at a later time. For other uses, the parts may be so arranged as to cause the circuit to be first opened and then closed. When used as a range timer, it is often desirable to have incorporated therein means for timing other kitchen operations, such as cooking on other circuits than the controlled oven circuit, or for indicating a time in which the oven circuit should be changed to increase or decrease the oven heat.

Range timers in order to be practically useful must be provided with an easily understandable control. means, otherwise the average housewife will find it easier to do without the range timer than to understand its operation. It is desirable to provide a range timer with controls which may be set in any order, and which will clearly indicate both the duration of the cooking period as well as'the time at which the cooking is to start and to cease. It is also desirable to provide controls which when once set, may not be changed by inadvertent manipulation or accidental displacement of other controls. It is also desirable to provide a starting and stopping control which is self clearing; that is after the device has been set and the circuit has been opened and closed in'accordance with such setting, the controls will not remain in their set condition for another cycle of operations, but must again be reset. This prevents inadvertent operation of the device during the succeeding twelve hours unless the controls are again manually set.

It is an object of my invention to provide an improved time switch of an inexpensive construction which is positive and accurate in its operation, and which is provided with legible and easily operating control means.

It is another object of my invention to provide improved time responsive means to actuate electrical contacts at a predetermined time and to restore the same to their original position at a later time.

A still further object of my invention is to provideimproved time responsive actuating be set for operation independently of, and without disturbing the condition or position of the contact members.

Another object is to provide improved contact means for a time switch of such construction that each separate contact unit is substantially identical to another and whereby the said units may be built up or arranged in a group of any reasonable number so that all may be actuated simultaneously by the same actuating means.

A further object is to provide an improved time switch wherein the controls are self-clearing.

Another object is to provide for a range time: improved means for measuring short intervals of time.

Still another object is to provide circuit control means, which may be operated automatically or manually, and interlocking means whereby inadvertent manipulation of the controls when set to one type of operation will not cause a change in that setting.

Other objects, features and advantages will become apparent as the description proceeds.

With reference now to the drawings wherein like reference numerals denote like parts:

Fig. 1 is a front elevation of a preferred embodiment of my invention, certain parts being broken away;

Fig. 2 is a. plan view showing the general or ganization of the device shown in Fig. 1, certain parts being omitted for purpose of clarity;

Fig. 3 is a rear sectional elevation taken along line 3-3 of Fig. 2;

Fig. 4 is a section taken along line 4-4 of Fig. 3;

Fig. 5 is a section taken along Fig. 3;

Fig. 6 is an elevation taken along the line 6-6 of Fig. 2;

Fig. 7 is a section of certain parts taken along line 1-1 of Fig. 6;

Fig. 8 is a section similar to Fig. 6 but showing the parts in a changed position;

Fig. 9 is a section similar to Fig. 5 but showing the parts in a diflerent position;

Fig. 10 is a section taken along line ill-i0 of Fig. 1; I

Fig. 11 is an elevation of the contact units taken along the section line H -I| of Fig. 2;

Fig. 12 is a detailed elevation of a modified control means;

Fig. 13 is a section taken along line I3i3 line 5-5 of means for electrical contact means which may of Fig. 12; and,

Fig. 14 is an elevation of certain parts shown in Fig. 12, but in a changed position.

With reference now to Figs. 1 and 2, reference numeral 28 indicates the front plate of the range timer which is associated with the rear plate 2| by means of spacing members 22. An intermediate plate 23 is spaced from the rear plate 2| by means of spacing members 24, and from the front plate by means of spacing members 25. A shell 25 is secured to the front plate 20, and serves to enclose certain of the parts mounted on the front plate. I A glass crystal 21 is mounted in the shell and exposes an annular clock dial 28 which is provided with the usual indicia thereon. A rotatable stop dial 29 is.

mounted centrally of the clock dial, and a start dial 30 is rotatably mounted rearwardly of the clock dial and the start dial. The stop dial is apertured as indicated at 3| to expose indicia 32 formed on the start dial. The start dial is provided With a pointer 33, and the stop dial is provided with a pointer 34. An hour hand 35 and a minute hand 36 are provided for cooperation with the clock dial 28. The hands and dial are shown in section in Fig. 10.

A setting knob 31 for the hands 35 and 36 extends from the shell 26, and setting knobs 38 and 39 for the start and stop dials, respectively, also extend through the shell. A switch control knob 40 is located at the right hand portion of the device as indicated in Fig. 1, and an alarm control knob 4| is located at the left hand portion.

A housing 42 which is indicated in Fig. 2 in dotted lines may be provided for the -device. A synchronous electric motor 43 is mounted on rear plate 2| and is positioned within the housing, and serves'to drive the clock hands, the switch actuating means, and the alarm for a short time interval measuring means, the motor being secured to the plate by means of screws 44.

The motor shaft 45 extends through the rear plate and is provided at its forward end with a pinion 46, which pinion as shown in Fig. 3 drives the mechanism through a series of speed reduction gears which are indicated as speed wheels 41, 49, and 53 and associated pinions 48, 50, 52 and 54. Pinion 54 meshes with and drives a wheel 55 which as will be hereinafter described, drives the alarm mechanism. A wheel 56 is driven by the pinion 52, and a pinion 51 secured to the wheel 56 drives a wheel 58 which is frictionally associated with the minute shaft 59 by means of the usual spider 60 and adapted to drive the same.

A hand setting shaft 6| is journalled in the rear and intermediate plates 2| and 23 and carries a pinion 62 which meshes with pinion 63 which in turn drives the wheel 64. A pinion 6-5 is staked to the minute shaft 59 as shown in Fig. and is provided with a hub 66 to which the spider 60 is secured, the wheel 58 being journalled on the hub and located between the spider and the pinion 65.

The pinion 65 meshes with the wheel 84 so that the minute shaft may be set by rotation of the hand setting knob 37. A pinion 61. which is secured to the wheel 64, meshes with the hour Wheel 68 so that the latter may be driven from the minute shaft. .The hour wheel 68 is mounted on a sleeve 69 which extends forwardly around the minute shaft 59. and carrie at its outer end the hour hand 35. The minute hand 36 is mounted on the minute shaft 59.

The frictional association of the wheel 58 with the minute shaft 59 permits the hands and the hour wheel to be set by manually rotating the setting knob 31. Certain parts of the contact actuating means hereinafter described are driven from the hour wheel so that their position corresponds with that of the hands.

As shown in Figs. 2 and 11, the contactin means are mounted in the recessed portions of two insulating blocks 10 and 'H, and comprise a stationary contact 12, 13, connected by a strip 14, 15 to a terminal screw 16, 11, respectively.

A movable contact 18,; 19 is provided for each,

of the insulating blocks 'lfl and II, respectively, each movable contact being carried on a spring member 80, 8|, which is connected by a con-' ducting strip 82, 83 to a terminal screw 84, 85; It will be seen that each insulating block carries a complete contact means and the two contact means may be employed to open both wires. of acircuit to the heating element.

A pin 8! extends through apertures in the two blocks and through apertures in the spring members 80 and 8|, the pin being provided with collars 88 and 89 which contact the spring members will be seen that any number of said blocks mayv be aligned side by side so that any number of circuits may be controlled by the actuating means, the =only difference being that a longer pin 81 provided with additional collars must be employed with additional contacting means. Studs 86 ex tend through the series, of insulating blocks and are threaded into the spacers 22 in order to hold the blocks in the correct position.

The pin 81 at one end abuts a pivoted contact actuating member 92 which includes a rock shaft 93 on which a spring 94 is located to bias the pin 81 and the contacts 18 and 19 to open circuit positions as shown in Fig. 5. When the pivoted actuating member is rotated in the counterclockwise direction against the bias of spring 94, the resiliency of the spring members 80 and 8| permits the circuit tobe closed. A projection 95 mounted on the actuating member 92 is engaged by one arm of an U-shaped member 96 which is pivotally mounted on a spacing member. A floating bar 91 is mounted on a headed stud 98 which extends forwardly of the rear plate, and the lower end of the floating bar is engaged by the U-shaped member 96 in such a manner as to cause retraction of the actuating member 92, thereby closing the circuits through the contacts. when the lower end of the floating bar is caused to move rearwardly. The position of the upper end of the bar is controlled by the actuating means hereinafter described to first close the circuit through the contacts, and then to open the same.

With the reference now to Fig. 6, a start shaft I00 is journalled in the front and rear plates and frictionally associated with the start knob 38, and a stop shaft |0l is journalled in the. front and rear plates and frictionally associated with the stop knob 39, the floating bar 91 being apertured to permit these shafts to extend therethrough. A spring I82, I03 is provided for each of the shafts I00, I 0|, the spring being confined between the rear plate and the floating bar to urge either end of the bar forwardly. A hub I04 is rotatably and slidably mounted on the guide shaft I08, the sleeve being provided with an annular groove by means of which it may engage the upper portion of the floating bar 91. A crowned washer I fits in the groove and serves as a bearing member between the fioating bar and the hub. A similar hub I together with a crowned washer I0! is rotatably mounted on guide shaft I09 and engages the lower portion of the floating bar 91. The guide shafts I08, I09 may be rotatably mounted in the front and rear plates 20. 2I.

Wheels H0, III are secured to hubs I04, I05, respectively, and mesh with the hour wheel 50, a fragmentary portion. of which is shown in Fig. 6 in dotted lines in order that the wheels H0, III may be driven at the rate of one revolution every twelve hours. the guide shafts I08, I 09, respectively, each wheel meshing with a pinion II 4, II 5 on the start setting shaft and stop setting shaft I00, IOI, re-

.spectively,-so that they may be manually rotated independentlv with respect to the clock driven wheels IIO, III. An aperture H8, H9 is provided in each of the wheels H2, H3 which is adapted at certain times to receive a pin I20, I2I which extends rearwardly from the wheels H0, III, respectively, so that either of the latter wheels are caused to be driven by the former.

When both the start and the stop shafts have been set so that the apertures H8 and H9 are angularly spaced by a predetermined distance from their respective pins I20 and I2I the wheels H0 and III will be rotated so that the pins will slide on the surface of the wheels H2, H3 until their respective pins drop into their corresponding apertures. The wheels H2, H3 will remain stationary due to the friction disks H8. H1, which are secured to the wheels I I2, I I3 and bear against the front plate 20. The contacting area between the friction disks and the front plate is of greater radius than the contacting area between the pins and the wheels H2. H3 so that sliding always takes place between the pins and the wheels. When the pins drop into their re s ective positions the friction between the friction disks and the plate is entirely relieved so that the load is released from the clock motor.

As shown in Figs. 6 and 7, the start wheel H2 is set for 3, and the stop wheel is set for 6 o'clock. The position of each of the Wheels H0, III, together with their respective pins I20. I2I, is 2 oclock. The position of the pins I20, I2| at 3 oclock is shown in Fig. 7 in dotted lines in which the pin I2I has moved into registry with the aperture H8 and permits the spring I02 to d splace the upper portion of the floating bar to the left so that the pin drops into the aperture, this position of the parts being shown in Fig. 8. During this motion of the bar 91, the bar is pivoted on the hub I05, and the lower end of the bar moves to the right causing the pivoted actuating member 92 to be rotated against the bias of spring 94 and the contacts to be closed. This position of the contacts is shown in Fig. 9.

At 6 oclock the pin l2I will move into registry with the aperture I I9, and permits the lower end of the bar 97 to be moved to the left by the spring I03, and thereby permitting the contacts to be again opened. It will be evident that as each pin drops into its respective aperture the wheels H2 and H3 will be driven by the clockwork and the apparatus will not repeat its automatic operation until the operator has again set the controls.

A collar I22, I23 is located on each of the shafts I00, IOI, respectively, to limit the displacement Wheels H2, H3 are mounted on of the floating bar as either end thereof snaps forwardly. A shock absorber spring I24, I25 is located on the shaft I00, IOI, between the collar I22, I23 and the pinion H4, H5. When the apparatus is set, the knobs 38 and 39 are pushed inwardly, one at a time against the bias of the springs I02 and I03, so that the pins I20 and I2I may be withdrawn from their respective apertures, and the knobs are then rotated so that the apertures are displaced from their respective pins into the desired set position. When the apparatus has been thus set the wheels IIO, III, are held away from the wheels H2, H3, and the floating bar 97 is caused to assume its set position as shown in Fig. 6.

A sleeve I21, as shown in Fig. 10, surrounds and is rotatably mounted on the hour sleeve 59, and at its forward end carries the stop dial 29. At its rear end is mounted a wheel I29 which meshes with the wheel I I3. A sleeve I26 is rotat ably mounted on the sleeve I21, and carries at end a wheel I 28 which is driven by the wheel I I2.

.It will be seen that the pointers 33 and 34 on the start and stop dials 30 and 29, respectively, serve to indicate to the operator the positions of the apertures H8 and H9. As the shaft I00 is rotated in the counter-clockwise direction as shown in Fig. 7, the wheel I28 and the start dial 30 will be rotated in the counter-clockwise direction until the desired setting is reached.

Referring now to Figs. 3, 4 and 5, the switch control knob 40 is provided with a hub portion I30 which is mounted on a stud I3I, extending forwardly from. the front plate 20. A cam plate I32 is non-rotatably associated with the knob 40 by means of a pin I33. A spring I34 biases the knob 40 and the cam plate into the automatic position. An arm I35 extends forwardly from the pivotal contact actuating member 92 through the apertured front plate 20 so that its forward end may be engaged by the cam plate I32. When the knob 40 is in the automatic position, as shown plate I32 so as to permit the knob to remain in its manual position until it is manually released by the operator. When the knob is set in the manual position, the circuit through the range timer is closed and the range may be operated manually by means of the usual control on the range itself. However, when the knob 40 is set in the automatic position, the circuit through the usual range control must be closed in order that the range timer may perform its function.

The interval timer or minute minder for measuring short intervals of time is enclosed in the left hand end of the range timer as viewed in Fig. l and is shown somewhat diagrammatically in Fig. 3. Since this interval timer forms no part of the invention covered hereby, it will not be described in detail. Sufiice it to state that the a scale graduated in minutes.

is then driven by the motor through wheel 55 and the bell MI is struck by a hammer at the end of the set interval.

In Figs. 12, 13, and 14, are shown a modification of the switch control means. A stud I70 is mounted on the front plate 20, and carries a lever III. A pin I13 on the cam plate I32 is adapted to engage one arm I12 of the lever I'II when the knob 40 is rotated from automatic to manual position. As shown in Fig. 14 this causes disa placement of the lever I'II so that its lower arm Ill will be urged into engagement with the stop shaft IN. A collar IN is provided on the stop setting shaft which, when the lever HI is in its displaced position, will prevent the stop setting shaft from being manually pushed inwardly. A spring I15 biases the lever I'll to a position wherein the lower arm ITI clears the collar I'M. A stop I16 serves to limit the position of the lever I'II.

It will be seen that when the knob 40 is in manual position the arrangement of the parts is such that when the stop setting knob 39 is pushed inwardly, the pivotedcontact actuating member 92 will be displaced so that arm I35 will clear the latch portion I36 on the cam I32, thereby permitting the spring I34 to rotate the cam plate to the automatic position. This is undesirable inasmuch as such change from manual to automatic operation may not be intended. Provision of the looking lever I'II prevents this from happening inasmuch as it prevents the stop setting knob 39 from being pushed inwardly when the switch control knob is set at manua On the other hand when the switch control'knob is set at automatic, and the controls on the rang are closed, itis obvious that an inadvertent setting of the" knob 40 to the manual position will cause the oven to be turned on. The interlocking means shown in this modiflcation prevents this from happening inasmuch as when the range timer is in its set position, the knob 39 is displaced inwardly in such a manner that the collar I'M obstructs the lever Ill, and consequently the knob 40 can not be latched in manual position inasmuch as the upper arm I12 will engage the pin I13 and prevent rotation of the knob into latched position.

In operation, the dial is normally cleared, the start and stop pointers, 33 and 34, coinciding with the hour hand. In this position, there is no friction dr'ag between the friction members H6, H1, and the front plate. Rotation of the hand setting knob 31 causes the hands of the clock as well as the position of the pins I20 and IZI to be set. The switch control knob 40 is first set to automatic to permit the contacts to be opened by the contact actuating member 92. ,The usual range control is then adjusted to closed circuit position at the proper degree of heat.

The start and stop dials may be set in any order by depressing and rotating the respective start and stop knobs. This causes either end of the floating bar 9! to be displaced rearwardly and to be maintained in such position until the apertures H8 and H9 are rotated away from their corresponding pins. Let it be assumed that at two oclock the operator desires to set the range timer so that'the oven will go on at three and be turned off at six oclock. By rotating the start knob 38 so that the pointer 33 on the start dial 30 points to three oclock. the aperture H8 is displaced from the pin I20 by an angular distance which is the equivalent of one hour. Similarly the stop setting knob 39 is pushed in and rotated until the pointer 34 on the stop dial 29 is opposite six oclock. This causes the aperture I I9 to be displaced from the pin I2I by an angular distance which is the equivalent of four hours. It Will be noted that the cooking time, or the interval between the start and stop settings, is indicated by the indicia on the stop dial 30, which indicia are exposed through the aperture in the start dial 29. Due to the construction hereinbefore described, setting can take place in either direction; that is the knobs can be rotated either way. I

At three oclock the pin I20 drops into the aperture I I8 and causes the floating bar 91 to be pivotally rotated about the hub I05. The backward movement of the remote end of the floating bar causes retraction of the contact actuating member 92, which in turn permits the contacts to close.

At six oclock, the pin I2I drops into the aperture I I9 which causes the pivoted actuating memher to again engage the contacts and to open them.

The switch control knob 40 may at any time be set to the manual position wherein it maintains the contact actuating member in the disengaged position without in any way affecting the timing mechanism. If it is desired to set the mechanism when the switch control knob is in manual position, it will be observed that depression of the stop setting knob 39 will cause the contact actuating member to be retracted sufficiently so that the arm I35 thereof will clear the hump or latch portion I36 on the cam plate I32. This permits the knob to return to its automatic position.

In the modification shown in Figures 12, 13, and 14 however, the interlocking lever I'l-I prevents this from taking place. inasmuch as the stop setting knob 39 is locked in its forward position when the switch control knob 40 is in its manual position. This prevents inadvertent opening of the circuit when cooking manually.

If it is desired to measure a shorter interval, the alarm control knob 4| can be rotated manually so that the indicia thereon will indicate the length of the interval to be measured. The alarm mechanism is then rotated by the motor through wheel 55 and will sound the alarm bell III at the end of the selected interval.

It is obvious that numerous changes and modiflcations may be made in the preferred embodiments which have been herein described, without departing from the spirit of my invention. It is understood however that this invention is not to be limited by the above description, but only by the following claims.

Iclaim:

1. Timing mechanism comprising two separate time driven releasing means adapted to be displaced seriatim in the same direction and disposed in side by side relationship. a rigid member associated with both of said releasing means, resilient means urging said rigid member against each releasing means, and circuit controlling mean engaged by one end of said rigid member for actuation thereby.

2. Timing mechanism comprising contact actuating means biased to open circuit position, two time actuated releasing means disposed in side by side relationship, and a floating bar associated with said releasing means and having a portion engaging said contact actuating means in such a manner that operation of one of said releasing means will cause said Contact actuating means to be displaced to closed circuit position. and operation of said second releasing means will cause said contact actuating means to be restored to its normal position.

3. A time switch comprising a contact member biased to closed position, a contact actuating member biased to maintain said contact member in open position, and automatic means to cause operation of said contact actuating member, said means including two independent time driven releasing means disposed in side by side relationship, and a floating bar engaged by said releasing means and having a portion engaging said contact actuating member for causing disengagement between said contact actuating member and said contact member at a predetermined time to close a circuit, through said contact member, and for causing engagement at a later predetermined time to open the circuit, and manually operated means for maintaining said contact actuating member in disengaged position whereby the circuit may be closed at will.

4. Timing mechanism comprising a time driven rotatable member, a manually rotatable member in coaxial relationship therewith, interlocking means to cause said manually rotatable member to be driven by said time driven member when rotatable cam means for latching said actuating member in closed position, and manually actuated setting means for said time responsive means which is associated with said contact actuating member in such a manner as to cause displacement thereof away from said cam means to unlatch the same.

6. Timing mechanism comprising a contact member biased to closed position, a contact actuating member biased to open position, time responsive means for causing disengagement of said actuating member from said contact member, manual means for latching of said actuating member into disengaged position, manually actuated setting means for said time responsive means, and an interlocking lever adapted to be displaced by said latching means into engagement with said setting means in order to prevent manual operation of the same when said actuating member is latched in disengaged position.

7. A time switch comprising time responsive driving means, two rotatable Wheels driven thereby and arranged in side by side r ionship with each other, two aper ured settin eels coaxially mounted with respect to ca wheels, 9. projection on each of said extending into contact with each of said setti wheels and adapted to hold each ir of driven and setting wheels in axially spac tionship, a bar contacting each of said driven wheels and being resiliently confined thereby when said wheels are maintained in spaced relationship to their corresponding setting wheels, friction means to maintain each of said setting wheels in a predetermined set position when the projections of the respective driven wheels contact the side surfaces of said setting wheels, and adapted to be released when the said projection drops into the said aperture so that said setting wheels may be driven by said driven wheels, and contact on said driven driven wheels means actuated by the position of one end of said bar to first close and then open a circuit at predetermined times.

8. Timing mechanism comprising two axially movable rotatable members, time responsive driving means for rotating each of said members, a pivotally mounted member having its pivoted support movable axially with one of said members and having a remote portion movable axially with the other of said members, yielding means biasing each of said rotatable members against a corresponding adjustable stop plate .for each, each plate being ineffective as a stop in one position of adjustment and effective in all other positions, and a circuit controlling device connected to said pivoted member, whereby axial movement of one of said rotatable members at a predetermined time will rock said pivoted member in one direction and axial movement of the other of said rotatable members at a predetermined time will rock said pivoted member in the opposite direction to operate said circuit controlling member.

9. Timing mechanism comprising two axially: movable rotatable members, time responsive driving means for rotating each of said members, a pivotally mounted member having its pivoted support movable axially with one of said members and having a remote portion movable axially with the other of said members, yielding means biasing each of said rotatable members against a corresponding adjustable stop plate for each, each plate being ineffective as a stop in one positron or. adjustment and effective in all other positons, and a circuit controlling device connected to said pivoted member whereby axial movement 01' said rotatable members one after the other at predetermined times will rock said pivoted member Inst in one direction and then in the opposite direction to open and close a circuit, and separate means to adjust the position or each or said stop plates which includes means to displace each or sald rotatable members against said yielding means.

lu. Releasing mechanism for a time switch comprising an axially displaceable rotatable member, time responsive drivlng means therefor, yielding means biasing said rotatable member against a manually rotatable stop plate, said plate being inenective as a stop in one position of adjustment and enectlve in all other positions, Il-ictlon means for maintaining sald stop stationary when eii'ective as a stop, means for releasing said Iriction means at the time at which it becomes ineffective as a stop, whereby said stop I plate may be subsequently rotated by said time rotating said stop plate with respect tosald time driven rotatable member.

out a member and a manually operable member in conical relationship therewith, interlocking means for each set for causing the manually rotatable member thereof to be driven by the time driven member when the latter is rotated to a predetermined position with respect to the former, an electric switch, means associated with the interlocking means of one of said sets of members to close said switch, and means associated with the interlocking means of the other set of members to open said switch.

' 12; .In a timing unit, an electric switch, a synchronous motor, operating means for said switch comprising a rotatable member driven by said motor and a rotatable member coaxial therewith and settable manually to predetermine the time 'of operation of said switch, friction means for holding said second member stationary when same has been manually set, interlocking means to cause said second member to be driven by said first member when the latter has been rotated to the position denoting the predetermined time of switch operation, and means controlled by said interlocking means for causing operation of said switch and for releasing said friction means to reduce the load on said motor. "'13; In atiming unit, a timing mechanism, a switch, actuating means for said switch including a member driven by said timing mechanism and ,a member manually adjustable to predetermine the time of operation of said switch, friction means for holding said manually operable member in set position, and means for releasing said friction means upon operation of said switch.v

14. In a timing unit, a timing mechanism, a switch, actuating means for said switch controlled by said timing mechanism, manually operable setting means for predetermning the time of operation of said switch including a visual indicator to indicate the set time, and means for driving said indicator from said timing mechanism following operation oi said switch. v

15. In a timing unit, an electric switch, a synchronous motor, operating means for said switch including a member driven bysaid motor, manually operable setting mechanism for adjusting the time of operation of said switch including a second member cooperating with said first member and an indicator to indicate the position of said second member, and means for driving said second member and said indicator by said motor following operation of said switch.

ARTHUR R. HUTT. 

